Effects of Irradiation on Survival and Growth of Listeria Monocytogenes and Natural Microflora in Vacuum-packaged Turkey Hams and Breast Rolls

The D10-values of L. monocytogenes in breast rolls and hams were 0.52 and 0.47 kGy, respectively. For breast rolls, the log10 reductions of L. monocytogenes following irradiation at 1.0 and 2.5 kGy were 1.5 and 4.7, respectively, while 2.0 and 5.5 for hams. The log10 reductions of APC in breast rolls following 1.0 and 2.0-kGy irradiation were 2.9 and 5.2 while that of hams was \u3c 10 CFU/cm2 after 1.0- and 2.0-kGy irradiation. In 2.0 kGy-irradiated hams, L. Monocytogenes grew to 4.82 log10 CFU/cm2 after 28 d storage at 4 °C, while APC increased to 2.98 log10 CFU/cm2, respectively. In breast rolls after 14 d storage, APC in 1.0 kGy-irradiated samples increased to 7.53 log10 CFU/cm2; and APC increased to 2.63 and 4.68 log10 CFU/cm2 for 2.0 kGy-irradiated breast rolls after 14 and 28 d storage. However, during the storage of breast rolls, L. monocytogenes grew slowly or even stopped to grow in both non-irradiated and irradiated breast rolls due to the competitive inhibition of natural flora in breast rolls. Irradiation greatly reduced L. monocytogenes and APC in turkey hams and breast rolls. However, at least 2.5 kGy irradiation is needed to achieve a 5-log reduction of L. monocytogenes in turkey hams and breast rolls. Some cells survived irradiation and grew during storage after lag phase. To control L. monocytogenes contamination in RTE turkey hams and breast rolls during storage, additional barriers, such as adding preservatives, are necessary in order to ensure the microbial safety of products following low-dose irradiation

Overcoming extreme-scale reproducibility challenges through a unified, targeted, and multilevel toolset

pre-printReproducibility, the ability to repeat program executions with the same numerical result or code behavior, is crucial for computational science and engineering applications. However, non-determinism in concurrency scheduling often hampers achieving this ability on high performance computing (HPC) systems. To aid in managing the adverse effects of non-determinism, prior work has provided techniques to achieve bit-precise reproducibility, but most of them focus only on small-scale parallelism. While scalable techniques recently emerged, they are disparate and target special purposes, e.g., single-schedule domains. On current systems with O(106) compute cores and future ones with O(109), any technique that does not embrace a unied, targeted, and multilevel approach will fall short of providing reproducibility. In this paper, we argue for a common toolset that embodies this approach, where programmers select and compose complementary tools and can effectively, yet scalably, analyze, control, and eliminate sources of non-determinism at scale. This allows users to gain reproducibility only to the levels demanded by specific code development needs. We present our research agenda and ongoing work toward this goal

Effect of Electron Beam Irradiation and Storage on the Quality Attributes of Sausages with Different Fat Contents

Sausages with different fat contents (16 or 29%) were purchased from local stores, vacuum-packaged in oxygen-impermeable bags, and irradiated at 0 or 5 kGy using a linear accelerator. The changes in quality attributes of irradiated sausages were determined during storage at 4°C. The 2-thiobarbituric acid-reactive substance values of sausages were not affected by fat content but were increased after irradiation (5 kGy). Storage for 60 d increased the 2-thiobarbituric acid-reactive substance values of nonirradiated sausages (P \u3c 0.05) but had no effect on irradiated sausages. The numbers of volatile compounds and the amounts of total volatiles were increased by irradiation in both the high-fat (29% fat) and low-fat (16% fat) sausages. Dimethyl sulfide was detected only in irradiated sausages, regardless of fat content (P \u3c 0.05), but it disappeared after 60 d of storage. Pentane and 1-heptene were detected only in irradiated samples after 60 d of storage. Low-fat sausages had greater L* values, but had lesser a* and b* values than high-fat sausages. Irradiation and storage had little effect on either the exterior or interior color (L*, a*, and b* values) of sausages. Fat content had no effect on the sensory variables of sausages, regardless of irradiation and storage. However, irradiated sausages had significantly stronger off-odors and off-flavors than nonirradiated sausages regardless of fat content (P \u3c 0.05). This indicated that fat content in sausages had a minimal effect on the quality of irradiated sausages during storage

Quality Characteristics of Irradiated Chicken Breast Rolls from Broilers Fed Different Levels of Conjugated Linoleic Acid

Dietary CLA treatment reduced color a*- and b*-values of cooked chicken breast rolls. Sensory panels rated the color of cooked chicken rolls with CLA treatments darker than the control. The production of CO in cooked chicken rolls increased dramatically after irradiation and was correlated with the increased redness of cooked chicken rolls after irradiation. Irradiation greatly increased volatile production and induced a metallic off-flavor in chicken rolls. The hardness of chicken rolls increased and juiciness decreased as the dietary level of CLA increased, and consumer preferred the color of cooked chicken rolls after irradiation to the nonirradiated ones. Although dietary CLA was somewhat positive in reducing pinkness, but negatively influenced to the eating quality of irradiated cooked chicken rolls

Effects of Electron Beam Irradiation and Antimicrobials on the Volatiles, Color and Texture of Ready-to-Eat Turkey Breast Roll

Adding 2% SL increased the hardness, springiness, cohesiveness, chewiness, and resilience of breast rolls. The color a* and b*values of turkey rolls with 2% SL added were significantly lower than those of the control, and this difference was maintained after irradiation and during storage. Breast rolls containing antimicrobials had more lipid oxidation than control. Irradiation promoted the formation of dimethyl disulfide and dimethyl trisulfide. Adding PB in breast rolls greatly increased the formation of benzene during irradiation. It also implies that certain spices or foods containing high amounts of phenolic compounds may not be suitable for irradiation. The combination of SL and SDA has a strong potential as an antimicrobial treatment for RTE meats, but low-dose irradiation (\u3c2.0 kGy) is preferred due to side effects of irradiation

Carrier-mediated magnetoelectricity in complex oxide heterostructures

While tremendous success has been achieved to date in creating both single phase and composite magnetoelectric materials, the quintessential electric-field control of magnetism remains elusive. In this work, we demonstrate a linear magnetoelectric effect which arises from a novel carrier-mediated mechanism, and is a universal feature of the interface between a dielectric and a spin-polarized metal. Using first-principles density functional calculations, we illustrate this effect at the SrRuO$_3$/SrTiO$_3$ interface and describe its origin. To formally quantify the magnetic response of such an interface to an applied electric field, we introduce and define the concept of spin capacitance. In addition to its magnetoelectric and spin capacitive behavior, the interface displays a spatial coexistence of magnetism and dielectric polarization suggesting a route to a new type of interfacial multiferroic

Intracisternal administration of NR2 subunit antagonists attenuates the nociceptive behavior and p-p38 MAPK expression produced by compression of the trigeminal nerve root

<p>Abstract</p> <p>Background</p> <p>We investigated the role of the central NMDA receptor NR2 subunits in the modulation of nociceptive behavior and p-p38 MAPK expression in a rat model with compression of the trigeminal nerve root. To address this possibility, changes in air-puff thresholds and pin-prick scores were determined following an intracisternal administration of NR2 subunit antagonists. We also examined effects of NR2 subunit antagonists on the p-p38 MAPK expression.</p> <p>Results</p> <p>Experiments were carried out using male Sprague-Dawley rats weighing (200-230 g). Compression of the trigeminal nerve root was performed under pentobarbital sodium (40 mg/kg) anesthesia. Compression of the trigeminal nerve root produced distinct nociceptive behavior such as mechanical allodynia and hyperalgesia. Intracisternal administration of 10 or 20 μg of D-AP5 significantly increased the air-puff threshold and decreased the pin-prick scores in a dose-dependent manner. The intracisternal administration of PPPA (1, 10 μg), or PPDA (5, 10 μg) increased the air-puff threshold and decreased the pin-prick scores ipsilateral as well as contralateral to the compression of the trigeminal root. Compression of the trigeminal nerve root upregulated the expression of p-p38 MAPK in the ipsilateral medullary dorsal horn which was diminished by D-AP5, PPPA, PPDA, but not Ro25-6981.</p> <p>Conclusions</p> <p>Our findings suggest that central NMDA receptor NR2 subunits play an important role in the central processing of trigeminal neuralgia-like nociception in rats with compression of the trigeminal nerve root. Our data further indicate that the targeted blockade of NR2 subunits is a potentially important new treatments strategy for trigeminal neuralgia-like nociception.</p

Spectral Correlation in Incommensurate Multi-Walled Carbon Nanotubes

We investigate the energy spectra of clean incommensurate double-walled carbon nanotubes, and find that the overall spectral properties are described by the so-called critical statistics of Anderson metal-insulator transition. In the energy spectra, there exist three different regimes characterized by Wigner-Dyson, Poisson, and semi-Poisson distributions. This feature implies that the electron transport in incommensurate multi-walled nanotubes can be either diffusive, ballistic, or intermediate between them, depending on the position of the Fermi energy.Comment: final version to appear in Phys. Rev. Let